Damped electrical relay



United States Patent 3,190,995 DAMPED ELETR1CAL RELAY George L. Brown, Evanston, Ill., assignor to C. P. Clare 3; Qompany, Chicago, Ill., a corporation of Delaware Filed Jan. 14, 1963, Ser. No. 251,191 2 Claims. (Cl. 200166) This invention relates to a damped electrical relay construction and, more particularly, to a damped electrical relay including a new and improved contact spring assembly or pile-up.

A telephone type relay commonly includes a plurality of contact springs mounted in spaced parallel positions on a relay frame or field structure by a pluralityof dielectric spacers which engage the springs adjacent one end there-of. The other ends of the springs carry contacts that are selectively moved into and out of engagement by displacing selected ones of the springs in response to the operation and release of the relay armature. In many relay constructions, there is a tendency for the spring or springs freed by the release of the relay to flag or oscillate with the result that the contacts initially separated by the release of the relay are momentarily moved into engagement. In the past, attempts have been made to reduce this flagging by damping or arresting movement of the released springs by the use of various types of detents. However, these detents frequently increase the size of the spring pile-up or are not capable of accurate and economical fabrication.

Accordingly, one object of the present invention is to provide a new and improved relay construction.

Another object is to provide a relay including a new and improved contact spring assembly.

Another object is to provide a contact spring assembly including means for preventing flagging of the contacts.

Another object is to provide a contact spring assembly including new and improved detent means for damping oscillatory movement of the contact springs.

Another object is to provide a contact spring assembly in which detent or damping means for certain of the contact springs are supported at the 'side of a dielectric means used to'position the contact springs so as to reduce the size or height of the assembly.

In accordance with these and many other objects, an embodiment of the invention comprises atelephone type relay including both a field structure carrying a winding and an armature movably mounted on the field structure. The contact spring assembly for the relay includes a plurality of contact springs supported in vertically spaced and generally parallel relationship on the field structure by a plurality of dielectric spacers which engage the contact springs adjacent one end thereof. The other ends of the contact springs are provided with contacts that are moved into and out of engagement in response to the actuation of selected ones of the springs by the relay armature. In order to prevent inadvertent movement of the contacts into engagement following their separation on release of the relay, at least some of the fixed contacts in the contact spring assembly are provided with damping or detent means that engage the fixed springs adjacent their free or contact carrying ends. These detents are secured to or supported from projecting portions formed on the fixed contact springs which project outwardly beyond the dielectric spacers so as not to increase the height of the contact spring assembly. These detent means can be fixedly secured to the fixed contact springs prior to the assembly of the spring pile-up to insure the proper positioning of the detent means and the contact springs.

Many other objects and embodiments of the present invention will become apparent from considering the following detailed description in conjunction with the drawings, in which:

FIG. 1 is an elevational view of a relay embodying the present invention;

. FIG. 2 is a top plan view of the relay;

FIG. 3 is aside elevational view of the relay; and

FIG. 4-is an exploded perspective view of a combined contact spring and detent used in the contact spring assembly for the relay.

Referring now more specifically to the drawings, therein is illustrated a relay, indicated generally as 10, which embodies the present invention and which includes a magnetic field structure 12 carrying a magnetic core 14 on which a winding assembly 16 is mounted. A generally L-shaped armature 18 is pivotally mounted on the field structure 12 by a pivot pin 26 and includes a depending arm 18a that is normally disposed adjacent but spaced from a pole face 14a on the magnetic core 14. The armature 18 also includes a pair of spaced arms 18b. (FIGS. 1 and 2) for actuating a contact spring assembly or pile-up indicated generally as 22.

The contact spring assembly 22 includes two groups of fixed contact springs 24 and movable contact spring 26' which are mounted in spaced parallel positions by a plurality of dielectric spacers or plates 28 which are interposed between adjacent ones of the contact springs 24 and 26. The assembled plurality of contact springs 24 and 26 and dielectric spacers 28 are secured in position on the field structure 12 by a plurality of threaded fasteners 30 which pass through suitably aligned openings in the elements 24, 26 and 28 and are threadedly received within openings in the field structure 12. The springs 24 and 26 are provided with one or more aligned contacts or contact elements 32 and 34, respectively, on their outer or free ends. The movable contact springs 26 are connected for operation by two separate rows (FIG. 3) of dielectric spacer tubes 36, the lowermost of each series of which rests on an end portion of one of the arms 18b on the armature 18.

When the relay 10 is actuated by energizing the wind ing 16, the armature 18 is pivoted in a clockwise direction (FIG. 1) about the pivot pin 20 so that the two series of dielectric spacer tubes 36 are moved upwardly to deflect or displace the movable contact springs 26 upwardly. This selectively moves contacts 32 and 34 into and out of engagement to selectively complete electrically conductive circuits between the springs 24 and 26. When the energization of the winding 16 is terminated, the displaced springs 26 act through the dielectric spacers 36 to pivot the armature 18 in a counterclockwise direction about the pivot pin 2t) so that the springs 24 and 26 and the contacts 32 and 34 carried thereon are returned to their normal positions. In certain relay constructions and under certain operating conditions, there is a tendency for the free ends of the fixed contact springs 24 carrying the contacts 32 to oscillate or flag so that adjacent ones of the contacts 32 and 34 are momentarily moved into re-engagement following their initial separation. This can produce spurious signals, and the contact spring assembly 22 includes novel means for preventing this flagging.

In the illustrated relay construction 10, each of the fixed position contact springs 24 that provides a make contact, i.e., each spring 24 that carries a contact 32 that is engaged by a contact 34 when the relay 10 is operated, includes an integrally formed projecting portion 24a that projects outwardly beyond the adjacent wall surfaces of the dielectric spacers 28 to support a damping or detent means 38. Each of the detent or damping means 38 includes :an end portion 38a that is rigidly secured to the support portion or projecting means 24a on the contact spring 24, as by spot welding. The opposite or free end of the detent 38 is provided With an arcuate or cut-out portion 38b terminating in a projecting portion 380. The

arcuate portion 38b accommodates the dielectric spacer Patented June 22, 1965 tubes 36, and the projecting portion 38a is adapted to engage the free end of the contact spring 24to which the detent 38 is connected in a position adjacent but spaced inwardly from the contact 32. The detents or damping means 38 are secured to the lower surface (FIG. 1) of the related fixed contact springs 24 so that the free ends of the contact springs 24 rest on the offset portions 38c of the detent means.

Therefore, when the relay is operated to deflect the armature 18 in .a clockwise direction about the pivot pin 20, the free end portions of the movable contact springs 26 are rnoved upwardly to place the contacts 34 carried thereon in engagement with the contacts 32' on the fixed contact springs 24. During this movement, the free ends of the contact springs 24 can be lifted out of engagement with the detents 38 to insure a low resistance contact between the contact elements 32 and 34. When the relay 10 is released and the spacer tubes 36 together with the connected movable contact springs 26 move downwardly, the contacts 32 and 34 are moved out'of engagement, and the free ends of the fixed contact springs 24 are free to follow the downward movement of the movable contact springs 26. However, when the free ends of the springs 24- engage the detent or damping means 38, the downward movement of the free ends of the springs is terminated.

Since the portion of the spring'24 extending beyond the end of'the detent element 38 to the right of the projecting portion 380 (FIGS. 1 and 2) is not flexible enough to permit the degree of continuing movement of the contact 32 carried thereon that would permit their re-engagement with the contact 34 on the movable contact spring 26, the detent elements 38 prevent lagging. Further, by being mounted at the side of the dielectric spacers 28 in the spring pile-up 22, the height of this assembly is not increased by the use of the detents 38. In addition, the mounting of the detent elements 38 on the projecting portions 24a of the fixed contact springs 24 prior to assembling the pile-up 22 permits these elements to be secured in proper aligned positions and insures the proper adjustment of these components.

Although the present invention has been described with reference to a single illustrative embodiment thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this invention.

What is claimed as new and desired to be secured by Letters Patents of the United States is: V

1. A contact spring assembly comprising a plurality of contact springs, dielectric means for supporting the springs in spaced and generally aligned positions, said dielectric means engaging said springs adjacent one end thereof, contact means carried on the other ends of the springs, projecting portions formed integral with at least some of the springs and extending transversely outwardly beyond the dielectric means, a plurality of elongated damping elements each having an end portion rigidly secured to one of the projecting portions and extending 1 generally parallel to the springs, each of said damping elements having an offset end portion at its other end adapted to engage the other end of the spring to which the damping means is secured.

2. A contact spring assembly comprising a plurality of fixed contact springs and a plurality of movable contact springs, at least one of said movable contact springs being cooperatively associated with at least one of said fixed contact springs, contact means adjacent one end of said springs, a plurality of dielectric plates respectively positioned between adjacent ones of said contact springs adjacent their other end, dielectric actuating spacer means between adjacent ones. of said movable contact springs intermediate said contact means and said dielectric plates for actuating said springs in unison, said fixed contact springs having projecting portions integral therewith extending transversely outwardly beyond said dielectric means, a plurality of metal damping elements each having an end portion welded to one of said projecting portions on the side thereof toward the cooperatively associated one of said movable contact springs, each of said damping elements having a cut out portion accommodating said dielectric actuating spacer means, and having a projecting portion adapted to engage the free end of its supporting fixed contact spring.

References Cited by the Examiner UNITED STATES PATENTS 2,945,107 7/60 Hufnagel 200-166 BERNARD A. GILHEANY, Primary Examiner. 

1. A CONTACT SPRING ASSEMBLY COMPRISING A PLURALITY OF CONTACT SPRINGS, DIELECTRIC MEANS FOR SUPPORTING THE SPRINGS IN SPACED AND GENERALLY ALIGNED POSITIONS, SAID DIELECTRIC MEANS ENGAGING SAID SPRINGS ADJACENT ONE END THEREOF, CONTACT MEANS CARRIED ON THE OTHER ENDS OF THE SPRINGS, PROJECTING PORTIONS FORMED INTEGRAL WITH AT LEAST SOME OF THE SPRINGS AND EXTENDING TRANSVERSELY OUTWARDLY BEYOND THE DIELECTRIC MEANS, A PLURALITY OF ELONGATED DAMPING ELEMENTS EACH HAVING AN END PORTION RIGIDLY SECURED TO ONE OF THE PROJECTING PORTIONS AND EXTENDING GENERALLY PARALLEL TO THE SPRINGS, EACH OF SAID DAMPING ELEMENTS HAVING AN OFFSET END PORTION AT ITS OTHER END ADAPTED TO ENGAGE THE OTHER END OF THE SPRING TO WHICH THE CLAMPING MEANS IS SECURED. 